Preliminary studies on some gram-positive bacterial infection in some fresh water fishes

Gram-positive bacteria cause a diseases in fishes and of a considerable importance specially in recent years.In this investigation 1321 fishes of various species and life stagesfrom each Tilapia (Oreochromis species) and Nile cat fish (Cgariepinus)which were collected from different localities in different seasons of theyear, were subjected to clinical and bacteriological examination todetermine the prevalence of some Gram-positive bacteria (Streptococcusspecies, Staphylococcus spp.and Cperfringensi infection. Morphological and biochemical identification of the. isolated : bacteria (Streptococcus species, Staphylococcus spp. and Cperjringens) were applied. Beside 423 apparently healthy Oiniloticus with avThe results of survey revealed that, the percentage of Streptococcusinfection a mong examined fish was (25.5_~), (29.~1 %) in C. gariepinusand (24.8%) in Tilapia/ The percentage of infection was highest (35.2%)in summer, followed by (32.1 %), (25.6%) and (5.9%) in autumn, springand winter seasons respectively I The Staphylococcus species infectionamong examined fishes were (26.9%), constituted by (32.4), (25.2%),(24.2%), and (22.7%) in Slimmer, autumn, spring and winter seasons